Fuel injection engine

ABSTRACT

In a four cycle, reciprocating piston, internal combustion engine, a mixture of fuel and air is forcibly injected into the combustion chamber during the engine&#39;&#39;s compression stroke. A variation in the timing of such injection is effected through variation in the angular relationship of an injection controlling cam follower to its actuating cam on the engine&#39;&#39;s main camshaft. Plural cams on a manually actuated rock shaft control not only such variation of the fuel injection timing, but also control spark advance, and measure and limit the fuel volume in the fuelair mixture which is injected.

United States Patent Wilson 1 Oct. 21, 1975 1 FUEL INJECTION ENGINE 3,166,057 1/1965 Konrad 123/90.16 6] Inventor: Ora E. Wilson, 3906 Holly Drive, 3,614,944 10/1971 Ulbmg 123/139 AY West, Holiday, Fla. 33589 Primary Examiner-Charles J. Myhre Flledi June 1974 Assistant ExaminerDaniel J. O'Connor [21] Appl. No.: 478,319 Attorney, Agent, or FirmRobert Henderson [52] US. Cl 123/139 AY; 123/139 AC; A T

' 2 123/139 B; 123/90'16 In a four cycle, reciprocating piston, internal combus- [51] [1.1L Cl. FQZM 39/00 tion engine a mixture of fuel and air is i l [58] new of Search 123/32 139 139 jected into the combustion chamber during the en- 123/139 139 139 139 3 gines compression stroke. A variation in the timing of 139 139 139 AY, 9016 90-2; such injection is effected through variation in the an- 74/569 gular relationship of an injection controlling cam follower to its actuating cam on the engines main cam- [56] References C'ted shaft. Plural cams on a manually actuated rock shaft UNIT STATES ATEN S control not only such variation of the fuel injection 1,066,939 7 1913 Ohlsson 123/139 B g, but also control par ad a and a u 1,897,044 2/1933 Elwell 123/139 AC and limit the fuel volume in the fuel-air mixture which 1,956,923 /1934 Jendrassik..... 123/139 AC is injected. 1,996,710 4/1935 Sass 12 3/139 AY 2,260,414 /1941 Thaheld 123/139 AY 5 Claims, 4 Drawing Figures l: 70 67 60 v 6! A 42 6 =2 I6 is h US. Patent Oct. 21, 1975 Sheet 1 of 3 3,913,548

FIG.1

US. Patent Oct.21, 1975 Sheet2 0f3 3,913,548

FIG.2

[Him-III U.S. Patent Oct. 21, 1975 Sheet 3 of3 3,913,548

FIG. 4

FUEL INJECTION ENGINE BACKGROUND OF THE INVENTION In most internal combustion engines, the fuel is mixed with air and atomized in a carburetor from which the atomized mixture is drawn into the engines combustion chamber by the actionof the engines piston on its intake stroke.

In most so-called fuel injection engines an injection pump delivers an atomized fuel charge into the intake manifold from which the charge is drawn intothe combustion chamber by the action of the engines piston on its intake stroke. Thus, in such prior fuel injection engines, the timing of injection is in fixed relation to the operation of the engines piston, leading to relatively inefficient engine operation.

The preesent invention derives improved, highly efficient operation by providing means for controlling the ratio of fuel to air in an injected charge and for varying, according to engine speeds, of the timing of the fuel injection, the spark advance, and the closing of the engines intake valve.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a largely schematic sectional view of a fuel injection engine according to this invention, the parts shown being largely limited to those having a direct relation to the improvements of this invention, and being shown as with the engines inlet valve closed.

FIG. 2 is of a generally similar character as FIG. 1, but shows operating parts as with the engines inlet valve open.

FIG. 3 is an enlarged vertical sectional view of the engines injection pump.

FIG. 4 is a largely diagrammatic presentation, which, with the following description, will make clear to those familiar with the subject art, the operative relationship of parts directly under manual control and parts directly effecting timed operation of fuel injection and operation of the engines intake valve as well as spark advance andconditioning of the injected fuel-air mixture.

DETAILED DESCRIPTION OF THE INVENTION First, although not illustrated, it should be understood that, as with all four cycle engines, the engine with reference to which this invention is disclosed and described has an exhaust valve, a crankshaft, and certain other parts which function in a well understood manner in an engine-which includesthis invention in the same manner as such parts function in engines not including this invention. Such parts are omitted from this disclosure to focus attention upon the parts which constitute this invention and bring about the important operating improvements of this invention. This description now turns to the present disclosure.

GENERAL CHARACTERISTICS OF THIS INVENTIONSENGIN E. Referring to FIG. 1, the engines power piston re ciprocates within acylindrical combustion chamber lil, formed in the engine's block 12. The. piston l O is suitably connected by a connectingrod to the engines crank shaft (neither being shown) in a well .known manner. I I I An intake valve 13, held closed be a compression coil spring 14, controls passage of air from an air intake duct into the combustion chamber 11 formed in the block 12 and an engine head 16. Toward one side of the engine head it is formed with a combustion chamber recess 17 into which projectsthe firing end .of a spark plug 18 suitably fixed in the wall of the head 16.

The spark plug is connected through adistributor to a source of electric energy in a well understood manner. THE ENGINES FUEL INJECTION PUMP An injection pump 19 is suitably bolted. onto the head 16, preferably directed over the spark plug 18 and the combustion chamber recess 17.

As best seen in FIG. 3, the pump-l9 comprises a housing 20 formed toward one side with a relatively large upwardly opening air cylinder 21 within which is carried a piston 22. Rigidly integral with a projecting, reduced upper end portion 23 of the piston 22 is a laterally projecting arm 24.

Toward the opposite side of the housing 20 is formed an upwardly opening bore 25, parallel to the cylinder 21, and'a counterbore 26 extending downwardly from the bore and opening into a mixing chamber 27 which is connected by a side passage 28 to the lower portion of air cylinder 21 and by a bottom passage 29 to the combustion chambers recess 17. 1

The bore 25 and counterbore 26 carry therewithin a fuel pumping plunger element 30v comprising the following rigidly integral parts, to wit: a fuel pumping piston 31 at its lower end working in the counterbore 26, an intermediate shoulder portion 32 sliding in and guided by the bore 25, a neck portion 33 extending upwardly from shoulder portion 32, a cap 34 at the upper end of said neck portion, and a finger 35 extending laterally from the shoulder portion 32 through and beyond a vertical slot 36 formed in the side wall of the pumps housing 20. I

The lateral arm 24 is formed with a bifurcated end portion 37 which underlies and engages the underside of the cap 34, and the neck portion 33 is encircled by a coil spring 38 which is compressed between the shoulder portion 32 of the fuel pumping plunger element 30 and the under side of the arm 24 of the piston A check valve ball 39, yieldably held by a spring 40 against the lower end of the counterbore 26 substan-- THE MEANS FOR OPERATING THE ENGINES INTAKE VALVE j While the spring 14 normally holds the valve 13 closed, that valve is opened throughcam action and, under varying engine speeds, is held open for time durations depending upon the engines operating speed.

The engine is provided with a primary camshaft 42, one camming lobe 43 of whichengages an upper surface of a pivotal valve opening arm 44. and forcefully presses said arm downwardly; and, as said arm is in engagement the upper end of stem 45.of the intake valve 13, the downward movement of the arm 44 re sults in downward movement opening the latter.

The duration of'th e holding of theintake valve 13 open is controlledby a releasable lock mechanism of the valve 13, thereby v nation of the e'ngiries o'peia'tioii, it shoudl -suffice here to note that the pis ton 22 and plunger 31 of pump 19 rise to take air-and fuel into the pump and descend to discharge a mixture of airand fuel through passage 29 into the recess l7 area of combustion chamber 11. The

extreme upper'andlower limits of movement of piston i 22 and plunger 31are shown respectively inFIGS. 1

enabling th e' end portions of said arms to interact for locking and unlocking of the valve 'l'3'with respect to its open condition. y I I During closed condition of said valve, as in FIG. 1, an end portion 52 of ;the arm.:46 engages an end portion 53 of'the arm 44 with no material operational effect upper surface of arm 44 to lock the latter and the valve 13,.in-open condition -of said valve until'such locking means arereleasedw- 1 Such releaseoccurs when the.rotation of the secondarycamshaft48brings thelatte'rs cam lobe 49 opera-- tionally against the arm 46, moving the latter, against the force-of spring 47,3'to disengage the top'.of arm 44, thereby'enablingthe arm 44 to rise, permittingvalve l3 to be closed and held-closed by the force of spring 14 until the next succeedingsengagement of cam lobe 43 with-the arm 44.

v g Aiifle iMiNG oF. C,LsINo 0F THEJNQTAKE}.

and 2.

"It should be'observed, however, that while piston 22 uninhibitedly pursues it'sdciwn stroke, the storke of plunger'3l may becontrollably limited in its downward movement by means ofa rockable fuel control lever 58 or'equiv'alenf mechanical device operable by a linkage rod 60. Said=rod is schematically shown as pivoted at Contrary tovthe common practice'of causing opening and closing of anengine s..intake valve under 'control of a single cam lobe on the engines camshaft, the present inventionincludes means, .dependent upon the e'n'gines speed, for varying'the tim'eof closing of the intake valve." i p Variation in the mentioned closing-time of intake valve l31arises from theifactthat the secondary camshaft 48 is driven by thei primary camshaft 42 through two intermeshing spirailly-tooth gears 54 and 55 (see FIG. 4) respectively key'ed upon thecamshafts 48 and 42. The. gearv 55 is fixedly keyed to the'primary camshaft 42 but gear. 54 is so slideably keyed to thesecondary camshaftl 54 as to be slideable therealong to some extent, while, nevertheless, the being constrained to turnwith. the secondarycamshaft.

Such sliding of gear 54 from its full line position to purely longitudinal shifting of the'control plunger 57 by" the operator of 4 the engine. Thus, the. operator may change-the angular relationship of the two gears 54 and 55 to vary the timing of engagement of cam lobe 49 with the locking arm 4 6 and thereby vary-the timing of the closing of valve 13 relatively to theopera ti'on of the engines-piston 1'0.

MEANS FOR TIMING THE OPERATIONOF. THE ver. INJECTION'PUMP As this specification includes a comprehensive explasliding -nonrotary movement upon two suitable sup-.

one end to a crank 66a on a rock shaft 66 and at its other end to the lever 58. Rocking movement of the rock shaft 66 under the operators control, as hereinafter explained, causes the'rod 60 to'pivot said levers free end '59 upwardly, "as in FIG. 1', into position to engage the unde'rsideof finger 35 to variably shorten the storke of plunger 31, which shortening is possible because of the fact that said plunger is only yieldably urged downwardly by .the spring 38. v 3

The means for actuating the piston 22 and plunger 31, best'understood from FIGS. 1 and 2, comprise an assembly ofa substantially verticala push rod 61 pivoted'at 62 =atfiits lower end to the reduced upper end portion 23 of pis'ton 22,'and pivoted 'atits'upper end at 63 to a substantially 'h'orizohtal red 64, The other end of rod'64 is formed as a'yoke 65 extending about a concentricportion ofamanually controllable rock shaft 66 which supports said other end of rod 64 while, nevertheless, being slideable within said yoke. The push rod 61 is yieldably urged downwardly by-a'tens'ioned spring 61a, and-rod-64 i's'yi'eldab'ly urge'd'rightwardly by a tensioned spring 64a.'-=

The'rod 64 responds as'afollower'fortwo cams. One

cam is in theform of-an eccentric portion 67 of the rockshaft 66; being disposed'at'one side of the yoke 65 Rocking movement of the rock shaft 66, if done, as seldom-, to,the extent of 180. from its'FIG. l angular positionto its FIG. 2-position, thus causes the eccentric 67 to engage'the follower 68 to "shift the rod 64 leftwardly from its-FIG. 1' position to its FIG. 2 position. Less than 180 rocking movement of the rock shaft 66, as is usually ,the case,- results,- of course, in a reduced shifting of the--rod,64.

The 'left end of the rod 64 (as viewed 'in the drawing) is caused -to rise and fall to operate the pump 19 through rod 61 by a cam lobe 69'on primary camshaft 42, which lobe engages a cam following projection 70 onth'e underside of-'rod"64. Itwill be understood, :by comparing FIGS 1 and 2, that turning of the rock shaft 66 under control of the operator of the engine causes eccentric ti7 to modify. the timing of operation of the pump l9;b,y varying the angular relationship of the projection 70 with respectjto the axis of the camshaft 42. MEANSFQR ROQKING .IHEE ROCKSHAET 66 The-rock'shaft 66 is'g'iven a limited degree of rocking movement uner control of the operator of the engine through the medium of the control plunger 57. This control plunger is shown schematically as carried for ports represented at 72 and 73,- such supports being suitably fixed upon the engines head 16.:A third rigid supportrepresented at 74, rockably carries one end portion 75 of the rockshaft66while the other end of i opposed face of the support 73. Thus, by foot or hand,

operation of the plunger 57, said plunger may be pushed rightwardly (as viewed in the drawing) from its indicated full line engine-idling position toward its broken line accelerating position, thereby turning the rockshaft 66 proportionately to the longitudinal movement of the plunger 57.

GENERAL COMMENTS In addition to the above-mentioned controlmeans on the rockshaft 66, the latter also carries an additional cam or eccentric 84 which may be employed in a well known manner (not shown) to control a distributor to suitably vary the timing of firing of the engines spark plug 18.

The engines primary camshaft 42 is driven in direct relation to the engines crankshaft (not shown) by a chain 85 (or equivalent belt) working over a, sprocket 55 to cause, for that engine speed, the most desirable timing of open duration of the intake valve 13 by the lobe 49 of the secondary camshaft 48. V

The rightward movement of the plunger 57 also turns the rockshaft 66, thereby causing eccentric 67 to push horizontal rod 64 leftwardly to secure, for the particular speed of the engine, the most desirable timing of fuel injection by the pump l9.-Such operaton of the wheel 86 (or equivalent pulley wheel) fixed upon the camshaft 42.

It is preferable, for smoothe engine operation to provide a suitable governor 87 on the primary camshaft 42 with a control'lever 88 foreasing the governors action as the engine is acclerated by the operator. This lever is shown in schematic FIG. 4 as pivoted at its lower end at 89 upon the engines head 16 and constrained to swing toward the governor by a collar 90 fixed to plunger 57 as the latter is pushed by the operator to accelerate the engine. During such acceleration, a boss 91 located toward the lower end of the lever 88 depresses a spring retainer 92 of the governor and a related spring 93 to disable the governor until the engine operates at running speed.

This engine differs from conventional four cycle engines chiefly in having means (1) for varying the period of time during which the intake valve is held open, (2) for varying the time of injection of fuel into the combustion chamber, (3) for controlling the volume of fuel so injected, and (4) for disabling or easing the effect of a governor during acceleration of the engine.

The four just mentioned features as well as spark control all stem from operation of the assembly of the plunger 57 and the rockshaft 66.

The engine is started in the usual manner by closing of an electric circuit (not shown) to the spark plug and operation ofa starting motor (also not shown). The operator ccontrols further engine operation by pushing control plunger 57 rightwardly to derive the desired engine speed.

The rightward movement of the plunger 57 to an extent depending upon the engine speed desired causes the yoke 56 to shift gear on the countershaft thereby altering said gears angular relationship to gear rockshaft 66 also controls the volume of the fuel charge by crank 66a; and also controls the spark timing, all as hereinbefore explained.

As it may sometimes occur, upon stopping of the engine; that, with other parts, the primary camshaft 42 may turn reversely for one revolution, more or less, it is desirable to provide a stationary tripping rod 94 which, upon reverse engagement of cam lobe 69 with extension portion of the rod 64, will cause the trip ping rod94 to engage tapering surface 95 of said extension portion and lift the rod 64 to enable the cam lobe 69 to pass underneath the extension portion 70 and thereby avoid damage to the rod 64 and perhaps to other related parts.

The precise sizes, shapes andangular positioning of the various cams, cranks, and/or eccentrics on their respective shafts is an ordinary engineering matter which those skilled in the subject art may handle with little or no difficulty. The same istrue of the matter of properly 1. In a four cycle, fuel injection{reciprocating piston,

internal combustion engine, camshaft m'e'fans operating in fixed relation'tbfthe' operating speed ofthe engine, injection timing means for timing the injectionof. a

combustible fuel charge into thegengines combustion chamber, said 7 injection timingv means comprising pumping means for forcing said fuel charge into said combustion chamber, a pump-actuating cam lobe on said camshaft means, cam following means coacting with said cam lobe to cause reciprocation of said cam following means with respect to said camshaft means, connecting means between said cam following means and said pumping means for communicating said reciprocation to said pumping means, and manually operably control means for shifting said cam following means to move a cam engaging portion of the latter means to and fro between radially different points of its coaction with said cam lobe and thereby controllably vary the timing of such fuel injection relatively to the cyclic operation of the engine; said pumping means including a spring-closed air intake valve and valve control means coacting with said manually operable control means for varying the time of closing of said air intake valve in relation to the varying of timing of the fuel injection; said valve control means comprising a valve opening lobe on said camshaft means, a valve opening arm coacting between the latter lobe and the air intake valve to open the latter, a pivotal locking arm spring-pressed into locking interference with said valve opening arm to hold the latter in valve opening position; secondary camshaft means, intermeshing spiral gears coacting between the two said camshaft means to effect driving of the secondary camshaft means by the other camshaft 7 means, said spiral gear of the secondary camshaft means being slidable axially relatively to the latter to I vary the angular relationships. of the two -said-gears, a

cam lobe.;on said secondary camshaft means, engageab le with said locking arm to -movethe latter clear of such locking'interferenc e whereby to permit said valve to-clos e; and aayoke portion of-said'manually operable means in engagementwith. said slideable' gear'to effect sliding thereof; the slidingmovement of the latter gear by said yoke being-proportionate to the-mentionedto and fro movement of said cam following means, whereby to coordinate the timing of operation of said pumping means with the timing of closing of said valve.

2. Injection jection timing means according to claim l,- said pumping means comprising a pump having separate, parallel, movable pistons for ingesting air and fuel into the pump, both saidpistonsbeing adapted for movement by said cam following means, said piston for fuel being yicldably ,moveable in ;its fuel charging stroke, and said manuallyhoperab le control means .includinga fuel control lever manually operable to various intercepting positions relatively tosaid fuel control piston whereby to control the fuel component of a fuelair mixture pumped into the engines combustion chamber. I I I 3. Injection timing means according. to claim 1, said manually operable controlmeans comprising an eccentric mechanism including an eccentric man ually turnable about an axis adjacent to said cam following means and an eccentric follower rigid with said cam-following means having a follower surfacee coacting with said eccentric to shift said cam following means to and fro between radially different points of its coaction with said pump-actuating car'n lobe, said pumping means comprising a pump having separate, parallel, movable I nge stingia'ir and fuel into the pumping M: both said pistoriis being adapted for movement by sa Qcam'followihgmeans, said piston for fuel being yieldabl y movable its fuel charging stroke, saidm 'anoperable control "means including a fuelcon'trol leveri'mjan ually operable to various intercepting positions relatively to said fuelcontrol 'pistonzwh'ereby to control the fuel component of a fuel-air mixture pumped into the engin e scombustion chamber, said cam following means including a relatively straight rod extending tangentially in opposite directions relatively to'said camshaft means, said rod being spring-urged at one endthereo'f in coaction with said eccentric mechanism to impart said to and fro movement to said rod endwisely of thelatter, said rod at its other end being spring-urged in on'edir'ection approximately parallel to the line of movement of said pumps parallel pistons, and said pump-actuating cam lobe coacting with said 7 rod to move said parallel pistons oppositely in direc- 4 tion.

4. Injection timing means according to claim 1, said manually operable controlmeans comprising a manuing with said fuel control lever, whereby operation of said control plunger and resultant rocking of said rock shaft proportionately regulate the air-fuel mixture, the timing of fuel injection, and thejtirning of opening of said air intake valve. 1 I n i 5. Injection timing means according to claim 4, further including"a governor, mounted upon said firstmen'tioned camshaft means, and governor-control means coacting between said manually operable eon trol plunger and said governor to coordinate the latters operation with the movementof said control plunger. 

1. In a four cycle, fuel injection, reciprocating piston, internal combustion engine, camshaft means operating in fixed relation to the operating speed of the engine, injection timing means for timing the injection of a combustible fuel charge into the engine''s combustion chamber, said injection timing means comprising pumping means for forcing said fuel charge into said combustion chamber, a pump-actuating cam lobe on said camshaft means, cam following means coacting with said cam lobe to cause reciprocation of said cam following means with respect to said camshaft means, connecting means between said cam following means and said pumping means for communicating said reciprocation to said pumping means, and manually operably control means for shifting said cam following means to move a cam engaging portion of the latter means to And fro between radially different points of its coaction with said cam lobe and thereby controllably vary the timing of such fuel injection relatively to the cyclic operation of the engine; said pumping means including a springclosed air intake valve and valve control means coacting with said manually operable control means for varying the time of closing of said air intake valve in relation to the varying of timing of the fuel injection; said valve control means comprising a valve opening lobe on said camshaft means, a valve opening arm coacting between the latter lobe and the air intake valve to open the latter, a pivotal locking arm spring-pressed into locking interference with said valve opening arm to hold the latter in valve opening position; secondary camshaft means, intermeshing spiral gears coacting between the two said camshaft means to effect driving of the secondary camshaft means by the other camshaft means, said spiral gear of the secondary camshaft means being slidable axially relatively to the latter to vary the angular relationships of the two said gears, a cam lobe on said secondary camshaft means, engageable with said locking arm to move the latter clear of such locking interference whereby to permit said valve to close; and a yoke portion of said manually operable means in engagement with said slideable gear to effect sliding thereof; the sliding movement of the latter gear by said yoke being proportionate to the mentioned to and fro movement of said cam following means, whereby to coordinate the timing of operation of said pumping means with the timing of closing of said valve.
 2. Injection jection timing means according to claim 1, said pumping means comprising a pump having separate, parallel, movable pistons for ingesting air and fuel into the pump, both said pistons being adapted for movement by said cam following means, said piston for fuel being yieldably moveable in its fuel charging stroke, and said manually operable control means including a fuel control lever manually operable to various intercepting positions relatively to said fuel control piston whereby to control the fuel component of a fuel-air mixture pumped into the engine''s combustion chamber.
 3. Injection timing means according to claim 1, said manually operable control means comprising an eccentric mechanism including an eccentric manually turnable about an axis adjacent to said cam following means and an eccentric follower rigid with said cam following means and having a follower surfacee coacting with said eccentric to shift said cam following means to and fro between radially different points of its coaction with said pump-actuating cam lobe, said pumping means comprising a pump having separate, parallel, movable pistons for ingesting air and fuel into the pumping means, both said pistons being adapted for movement by said cam following means, said piston for fuel being yieldably movable in its fuel charging stroke, said manually operable control means including a fuel control lever manually operable to various intercepting positions relatively to said fuel control piston whereby to control the fuel component of a fuel-air mixture pumped into the engine''s combustion chamber, said cam following means including a relatively straight rod extending tangentially in opposite directions relatively to said camshaft means, said rod being spring-urged at one end thereof in coaction with said eccentric mechanism to impart said to and fro movement to said rod endwisely of the latter, said rod at its other end being spring-urged in one direction approximately parallel to the line of movement of said pump''s parallel pistons, and said pump-actuating cam lobe coacting with said rod to move said parallel pistons oppositely in direction.
 4. Injection timing means according to claim 1, said manually operable control means comprising a manually operable, longitudinally shiftable, control plunger, constrained against angular movement, a rock shaft constrained against longitudinal movemEnt and coaxial with respect to said control plunger, intermeshing spiral gearing on said plunger and rock shaft constraining the latter to rock in response to longituddinal shifting of said plunger, cam means on said rock shaft coacting with said cam following means to impart said to and fro movement to the latter means, a fuel control lever coacting with said pump to control the mixture of air and fuel discharged by the pump into the engine''s combustion chamber, and cam means on said rock shaft coacting with said fuel control lever, whereby operation of said control plunger and resultant rocking of said rock shaft proportionately regulate the air-fuel mixture, the timing of fuel injection, and the timing of opening of said air intake valve.
 5. Injection timing means according to claim 4, further including a governor, mounted upon said first-mentioned camshaft means, and governor-control means coacting between said manually operable control plunger and said governor to coordinate the latter''s operation with the movement of said control plunger. 